Added a volume slider to the inspector for the audio manager, so we can silence the game during testing if audio is not needed

Assets/Scripts/AudioManager.cs

@@ -31,6 +31,13 @@ public class AudioManager : MonoBehaviour
         }
     }
 
+    [SerializeField, Range(0, 1)]
+    private float masterVolume = 1f;
+
+    private float prevMasterVolume;
+
+    private FMOD.ChannelGroup masterChannelGroup;
+    
     void Awake()
     {
         // Ensure FMOD is initialized the moment Instance is accessed
@@ -43,6 +50,20 @@ public class AudioManager : MonoBehaviour
         InitFmod();
     }
 
+    void Update()
+    {
+        if (!fmodSystem.hasHandle() || !masterChannelGroup.hasHandle())
+            return;
+
+        if (!Mathf.Approximately(masterVolume, prevMasterVolume))
+        {
+            masterChannelGroup.setVolume(masterVolume);
+            prevMasterVolume = masterVolume;
+        }
+        
+        masterChannelGroup.getVolume(out masterVolume);
+    }
+
     void OnDisable()
     {
         // Ensure FMOD gets closed before hot reload
@@ -85,6 +106,11 @@ public class AudioManager : MonoBehaviour
 
         result = fmodSystem.init(MaxVirtualChannels, FMOD.INITFLAGS.VOL0_BECOMES_VIRTUAL, IntPtr.Zero);
         CheckFmodResult(result, "FMOD.System.init");
+
+        result = fmodSystem.getMasterChannelGroup(out masterChannelGroup);
+        CheckFmodResult(result, "FMOD.System.getMasterChannelGroup");
+        masterChannelGroup.setVolume(masterVolume);
+        prevMasterVolume = masterVolume;
     }
 
     private void CheckFmodResult(FMOD.RESULT result, string cause)